“Wisdom teeth” is a Chinese medical term that is familiar to the general public and is known in Western medicine as “blocked teeth”. An obstructed tooth is one that grows and erupts with resistance. There are generally two types of resistance: one is bone resistance and the other is resistance from the adjacent teeth. Many patients ask their doctors at the time of consultation if they can be removed without surgery. The extraction of an obstructed tooth is unique and it is normal for the average patient not to have a deep understanding of its characteristics. Many patients regard the extraction of an obstructed tooth as the extraction of a normal tooth, although some of them are not very different from the extraction of a normal tooth, but the extraction of an ambiguous obstructed tooth must be operated. However, surgery is necessary to remove an obstructed tooth that is only partially exposed beyond the gums or is completely buried, with the crown surface of the obstructed tooth covered with thick bone in the distal center (posterior), while the proximal center (anterior) of the obstructed tooth is stuck by a neighboring tooth. The purpose of the procedure is to remove the bone resistance, and the standard name for this procedure is “flap removal extraction”. Removal of bone resistance allows for smooth extraction of the blocked tooth, shortens the operative time, reduces the damage to the adjacent teeth, and allows for rapid wound healing. If the surgery is not performed, the following problems may occur: 1. long extraction time and difficulty. 2. 2. Easy to break the root and hollow out the root to increase the damage. 3. Damage to neighboring teeth or lead to loosening of neighboring teeth. 4. Prolonged extraction may lead to slow healing of the extraction wound or even “dry socket”, long duration of pain and other symptoms. To use an analogy, if there are three walls close together, and we need to remove the middle wall while keeping the two sides untouched, the removal of the middle wall will be very difficult and take a long time. If we first remove the useless wall on the marginal side (which corresponds to the bone covering the distal-middle surface of the crown of the interrupted tooth), the removal will go smoothly. And there is no damage to the useful wall (equivalent to the adjacent tooth) on the other side.